28. Marvin the Paranoid Android - In the 2005 film, 'The Hitchhiker’s Guide to the Galaxy,' Marvin the Paranoid Android had such a big brain and strong AI that he just felt too much. The dark humor of a depressed robot having an existential crisis was impeccably portrayed by the late Alan Rickman.

25. Xenomorph XX121 - The main character and creature of the 'Alien' saga is absolutely petrifying. Both the visual effects and the concept of Xenomorph XX121 will always scar and amaze those who watch 'Alien'.

23. Luke Skywalker - 'Star Wars' saga alumni, Luke Skywalker (Mark Hamill) was the protagonist in the original film trilogy. As main figure in the Rebel Alliance, he trained in the Force and became a Jedi Knight.

21. E.T. The Extra-Terrestrial - One of the cutest and kindest of all the sci-fi characters would have to be E.T. A tiny Drew Barrymore and her siblings attempt to help the weird little alien to escape Earth and get back home.

Immortan Joe's best enforcer, commander of his war rig, and a fierce warrior, Furiosa, played by Charlize Theron in 'Mad Max: Fury Road,' is commissioned with returning escaped women to her oppressive master.

Instead, she heads a biblical race against all of his warriors to lead the ladies to their freedom.

19. T-800 - Arnold Schwarzenegger's role in 'Terminator 2' as the T-800 portrays the rare, terrifying and heartwarming role of a killer robot learning human emotion, but realizing he can never have it himself.

'The Day The Earth Stood Still' of 1951 was revolutionary in its day. In contradiction to H.G Wells' 'The War of the Worlds,' this film depicts an alien attempting to teach Earth to reduce warfare. The pacifist alien was called Klaatu, and was played by Michael Rennie.

Throughout the 'Back To The Future' trilogy, this unlikely duo—Marty, a cool teenager of the '80s, and Doc, a brilliant, over-caffeinated professor—travel back and forth in time trying to correct the errors of Marty's first time-traveling goal of graduating and getting the girl.

The roles were played by Michael J. Fox and Christopher Lloyd respectively.

'Star Wars' saga's Boba Fett, portrayed by Jeremy Bulloch, was supposed to be one of the most dangerous men in the galaxy, ready to get brutal at a moment's notice. He known for saying very little and for his distinct T-shaped visor.

'RoboCop' is one of those sci-fi movies that was inevitable: a secret organization gives a man a second chance at life by rebuilding him as a robot. But not just any robot, Alex Murphy became RoboCop, programmed to fight crime.

This story follows RoboCop as his memories begin to resurface and his human side wants revenge. The role was played by Peter Weller (1987) and later Joel Kinnaman (2014).

HAL 9000 in '2001: A Space Odyssey' was decades ahead of its time. Sci-fi during this time focused on aliens and atomic weapons, but a sentient computer villain was far from everyone's minds until Douglas Rain voiced the terrifying A.I. system.

'Guardians of the Galaxy' power couple, Rocket (an anthropomorphic raccoon) and Groot (a tree-like being with limited language) were an odd pairing of outcasts that got the job done, with some comedy along the way.

Groot was voiced by Vin Diesel, and Rocket was voiced by Bradley Cooper, with motion action by Sean Gunn.

3. Han Solo - Played by Harrison Ford, Han Solo of the 'Star Wars' saga became the lovable rogue that everyone wished they could be. With the exception of his friend Chewbacca, the loner and smuggler only looked out for himself.